Method for producing high-silicate inorganic fibers of rocks

ABSTRACT

The present inventions relate to the means of production of high-silicate inorganic fibers of natural acidic rock minerals and also to products manufactured of said fibers, namely: continuous, staple fibers and scaly particles. In each variant of the M dacite or rhyodacite, granite or rhyolite, or a rock comprising mostly sand with silicon oxide content equal or exceeding 73% are used as a rock. The present inventions aim at proposing the means for producing inorganic fibers of natural acidic rock minerals and also the products manufactured of said fibers, namely: continuous, staple and coarse fibers and fine scaly particles having increased strength, corrosion and temperature resistance. This objective is attained by creating conditions for removing foreign inclusions, having high melting and boiling temperatures, from the melt by way of using rocks with higher silicon oxide (SiO 2 ) content and, therefore, higher melting points, as raw materials. This enables removal of most of foreign inclusions from the melted rock to the atmosphere.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the means of production ofhigh-silicate inorganic continuous, staple and coarse fibers, and scalyparticles of natural acidic rock minerals and also to productsmanufactured of said fibers, namely continuous, staple and coarse fibersand scaly particles.

2. Description of Related Art

The use of high-silicate inorganic fibers, made of natural acidic rocks,as raw materials, enables production of ecologically safe, resistant toatmospheric effects construction materials, which may serve assubstitutes for asbestos, glass, metal, wood, etc. Therefore, the needin such materials is increasing.

In terms of silicon content, the rocks are divided into: ultrabasic (1),basic (2), medium (3), and acidic (4). There are many publications andpatents, both national and foreign ones, describing methods andarrangements for obtaining inorganic fibers of rocks 1, 2, 3. Meanwhile,the author is not aware of any publications or patents describingmethods and arrangements for obtaining inorganic fibers of acidic rocks(4). In fact, predominance of one of the main silicon (Si) oxides in therock contents results in significantly altered properties of fibersobtained thereof, namely, in terms of strength, heat and chemicalresistance. For example, high-silicate glass fiber S-2, which comprisesover 95% of silica SiO₂ and is obtained by way of treating glass fiberwith hot acid, is 40% stronger that the glass E with 55% content ofSiO₂. Therefore, proposing means for using acidic rocks as rawmaterials, with a view to their almost inexhaustible deposits in theEarth, will enable production of high-module composite materials whichwould be much cheaper compared to cost intensive, expensive method ofproducing high-silicate glass fiber S.

There is known the method of producing continuous fiber of rocks,including the operations of rock fragmentation, melting in a meltingfurnace and drawing of continuous fiber from the melt through spinneret(Russian Federation Patent 2102342, IPC 6 C03B37/00, publication date 20Jan. 1998). In the described method the rocks used are basalt grouprocks, from basic to medium in contents, and the temperature in thefurnace is in the range of 1500 to 1600° C.

The fibers produced with the use of this method have insufficientrupture strength due to presence of foreign inclusions with meltingpoint higher than the melting temperature of the general mass of therock.

A method of continuous high-silicate inorganic fibers production ofrocks including the operations of fragmented rocks feeding to a meltingfurnace, rock melting, melt homogenization, further stabilization of themelt in the melting furnace feeder, fiber drawing, lubricating andwinding onto bobbins is disclosed in Ukraine Patent No. 10762, IPC 6C03B 37/00, publication date 25 Dec. 1998, bulletin No. 6.

The drawback of the described method is in that continuous fibersproduced of andesite rock using this method have insufficient rupturestrength caused by the presence of foreign inclusions, which can not beremoved from the melt due to insufficient temperature range limited bythe boiling point of the general mass of fractured rock. Suchinsufficient strength causes decreasing of the fibers length, theirbreaking in the process of winding onto bobbin, which limit thetechnological potential of the method.

A method of staple fibers production of rocks including the operationsof fragmented rocks feeding to a melting furnace, rock melting, melthomogenization, further stabilization of the melt in the melting furnacefeeder, and obtaining the staple fiber of melt flowing out of spinneretis disclosed in D. D. Dzhigiris, A. K. Volynskyi, P. P. Kozlovskyi, Yu.N. Dem'yanenko, M. F. Makhova, G. M. Lizogub. Fundamentals of basaltfibers production technology and basalt fibers properties.—In thecollection of scientific papers: Basalt fiber composite materials andstructures.—Kiev: Naukova Dumka.—1980—P. 54-81.

The drawback of the described method is in that staple fibers producedwith the use of this method have insufficient rupture strength caused bythe presence of foreign inclusions, which can not be removed from themelt due to insufficient temperature range used that is limited by theboiling point of the general mass of fractured rock. Such insufficientstrength causes decreasing of the fibers length, which limit thetechnological potential of the method.

A method including the operations of fragmented rocks feeding to amelting furnace, melting, melt homogenization, further stabilization ofthe melt in the melting furnace feeder, and obtaining the scalyparticles of melt flowing out of spinneret is disclosed in RussianFederation Patent No. 1831856, IPC 6 C03B37/02, B22F9/02, publicationdate 27 Mar. 1995, bulletin No. 9.

The drawback of the described method is in that scaly particles producedaccording to this method have insufficient chemical resistance andrupture strength caused by the presence of foreign inclusions, which cannot be removed from the melt due to insufficient temperature range usedthat is limited by the boiling point of the general mass of fracturedrock. Such insufficient strength and chemical resistance limit thetechnological potential of the method. Another drawback of the method isimpossibility to control fractional composition of scaly particlesobtained. Thus, the output percentage of homogenous fraction of neededdispercity and thickness of scaly particles turns to be low.

A production line comprising rock dosing unit, melting furnace, feeder,spinneret with the feeder for outputting the fiber, mechanism forapplying a lubricant onto fibers and bobbin for winding the fibers isdisclosed in Russian Federation Patent No. 2118300, IPC 6 C03B 37/00,publication date 27 Aug. 1998.

The drawback of the described production line is in insufficientstrength of fibers produced thereon. The reason is primarily in meltingfurnace operating temperature range limited by 1450° C. At thistemperature it is not possible to remove inclusions from the melt. Afterobtaining and cooling the fibers such inclusions become tensionconcentrators and cause early destruction of a fiber, for instance, whena fiber is wound on a bobbin.

Continuous fiber produced of natural rock materials is disclosed inUkraine Patent No. 10762, IPC 6 C03B 37/00, publication date 25 Dec.1998, bulletin No. 6.

Described fibers have insufficient rupture strength due to foreigninclusions present there.

Staple fiber produced of rocks is disclosed in D. D. Dzhigiris, A. K.Volynskyi, P. P. Kozlovskyi, Yu. N. Dem'yanenko, M. F. Makhova, G. M.Lizogub. Fundamentals of basalt fibers production technology and basaltfibers properties.—In the collection of scientific papers: Basalt fibercomposite materials and structures.—Kiev: Naukova Dumka.—1980—P. 54-81.

But it does not appear possible to produce staple fiber of acidic rocksaccording to the proposed method due to low temperature in the furnaceand large quantity of foreign inclusions.

Described staple fibers have large quantity of non-fibrous inclusionsand insufficient length of fibers, which limit the technologicalpotential of described staple fibers.

Fine scaly particles produced of natural rock materials are disclosed inRussian Federation Patent No. 1831856, IPC 6 C03B37/02, B22F9/02,publication date 27 Mar. 1995, bulletin No. 9.

Described fine scaly particles have insufficient strength due to foreigninclusions present therein.

SUMMARY OF THE INVENTION

The present inventions aim at proposing the means for producinginorganic fibers of natural acidic rock minerals and also the productsmanufactured of said fibers, namely: continuous, staple and coarsefibers and scaly particles possessing increased rupture strength,corrosion and temperature resistance. This objective is attained bycreating conditions for removing foreign inclusions, having high meltingand boiling temperatures, from the melt by way of using rocks with highSiO₂ content and, therefore, higher melting points, as raw materials.This enables heating until removing of most of foreign inclusions fromthe melted rock.

The objective is attained by the first variant of the proposed method,which, like the known method of producing inorganic continuous fibers ofrock, comprises operations of loading fractured rocks to meltingfurnace, rocks melting, melt homogenization, further stabilization ofmelt in melting furnace feeder, fiber drawing, lubricating and windingonto a bobbin, wherein, according to the invention, dacite or rhyodaciteis used as a rock, prior to loading to the melting furnace the rock isheated up to temperature between 700 and 910° C., kept at thistemperature during 5 to 15 minutes until removal of chemically boundwater and burning up organic components, then the rock is subjected tomechanical-catalytical activation until obtaining particles of not morethan 15 μm in size and is heated to temperature between 2105 and 2200°C. until obtaining the melt with amorphism degree of not less than 96%and isolation of not melted quartzites from the melt, furtherhomogenization and stabilization of the melt are performed at thetemperature 1420 to 1710° C. until obtaining the melt with viscositybeing not less than 130 decipoise, and fibers are drawn from the meltzone located below the surface layer.

The objective is also attained by the second variant of the proposedmethod, which, like the known method of producing staple fibers of rock,comprises operations of loading fractured rocks to melting furnace,rocks melting, melt homogenization, further stabilization of melt inmelting furnace feeder and obtaining staple fiber from the melt flowingout of spinneret, wherein, according to the invention, dacite orrhyodacite is used as a rock, prior to loading to the melting furnacethe rock is heated up to temperature between 700 and 910° C. and kept atthis temperature during 5 to 15 minutes until removal of chemicallybound water and burning up organic components, then the rock issubjected to mechanical-catalytical activation until obtaining particlesof not more than 15 μm in size and is heated to temperature between 2105and 2200° C. until obtaining the melt with amorphism degree not lessthan 96% and isolation of not melted quartzites from the melt, furtherhomogenization and stabilization of the melt are performed at thetemperature 1420 to 1710° C. until obtaining the melt with viscosity notless than 130 decipoise, and staple fibers are obtained by way ofinflating the melt flowing out of the spinneret.

The objective is also attained by the third variant of the proposedmethod, which, like the known method of producing inorganic fine scalyparticles of rock, comprises operations of loading fractured rocks tomelting furnace, rocks melting, melt homogenization, furtherstabilization of melt in melting furnace feeder and obtaining scalyparticles from the melt flowing out of spinneret, wherein, according tothe invention, dacite or rhyodacite is used as a rock, prior to loadingto the melting furnace the rock is heated up to temperature between 700and 910° C. and kept at this temperature during 5 to 15 minutes untilremoval of chemically bound water and organic components burning up,then the rock is subjected to mechanical-catalytical activation untilobtaining particles of not more than 15 μm in size and is heated totemperature between 2105 and 2200° C. until obtaining the melt withamorphism degree not less than 96% and isolation of not meltedquartzites from the melt, further homogenization and stabilization ofthe melt are performed at the temperature 1420 to 1710° C. untilobtaining the melt with viscosity being not less than 130 decipoise, andscaly particles are obtained by way of fracturing the melt streamflowing out of the spinneret.

The authors have experimentally determined the optimum operatingconditions for implementation of the methods of producing high-silicateinorganic continuous, staple fibers and fine scaly particles of rocks ofdacite or rhyodacite type. In particular, in case of heating the rawmaterial to temperature below 700° C. and keeping it for less than 5minutes, the quality of fibers and fine scaly particles so obtainedturns to be lower than required, because further obtained melt willcontain unmelted, fragile inclusions sparingly soluble in the melt,which significantly decrease the quality of the product obtained.Preliminary heating at the temperature over 910° C. during more than 15minutes is not justified economically. Obtaining the particles with thesize over 15 μm in the process of mechanical-catalytical treatment wouldcomplicate preparing of a homogenous melt and result in higher furthercosts for its heating in order to obtain the melt. Temperatures below2105° C. at the stage of obtaining the melt do not lead to removing mostof foreign solid inclusions, namely quartzites, from the melt andproducing the melt with optimum amorphism degree, i.e. not less than96%. Heating up to the temperature over 2200° C. have practically noeffect on quality of the product obtained and, therefore, is notjustified economically. It is practically impossible to producehomogenized and stable melt with optimum viscosity, i.e. not less than130 decipoise, at the temperature below 1420° C., while heating up tothe temperature over 1710° C. shortens the feeder and spinneret servicelife because the melt contains active substances causing destruction offeeder refractory materials into particles which obstruct (block up) thespinnerets.

The objective is also attained by the fourth variant of the proposedmethod, which, like the known method of producing high-silicateinorganic continuous fibers of rock, comprises operations of loadingfractured rocks to melting furnace, rocks melting, melt homogenization,further stabilization of melt in melting furnace feeder, fiber drawing,lubricating and winding onto a bobbin, wherein, according to theinvention, granite or rhyolite is used as a rock, prior to loading tothe melting furnace the rock is heated up to temperature between 750 and950° C. and kept at this temperature during 20 to 30 minutes untilfracturing of conglomerates and removal of water vapors, then the rockis subjected to mechanical-catalytical activation until obtainingparticles of not more than 10 μm in size and is heated to temperaturebetween 2110 and 2500° C. until obtaining the amorphous melt, furtherhomogenization and stabilization of the melt are performed at thetemperature 1500 to 1750° C. until obtaining the melt with viscositybeing not less than 145 decipoise, and fibers are drawn from the meltzone located below the surface layer.

The objective is also attained by the fifth variant of the proposedmethod, which, like the known method of producing staple fibers of rock,comprises operations of loading fractured rocks to melting furnace,rocks melting, melt homogenization, further stabilization of melt inmelting furnace feeder, obtaining of the staple fiber of the meltflowing out of the spinneret, wherein, according to the invention,granite or rhyolite is used as a rock, prior to loading to the meltingfurnace the rock is heated up to temperature between 750 and 950° C. andkept at this temperature during 20 to 30 minutes until fracturing ofconglomerates and removal of water vapors, then the rock is subjected tomechanical-catalytical activation until obtaining particles of not morethan 10 μm in size and is heated to temperature between 2110 and 2500°C. until obtaining the amorphous melt, further homogenization andstabilization of the melt are performed in the melting furnace feeder atthe temperature 1500 to 1750° C. until obtaining the melt with viscositybeing not less than 145 decipoise, and staple fibers are obtained by wayof inflating the melt flowing out of the spinneret.

The objective is also attained by the sixth variant of the proposedmethod, which, like the known method of producing high-silicateinorganic fine scaly particles of rock, comprises operations of loadingfractured rocks to melting furnace, rocks melting, melt homogenization,further stabilization of melt in melting furnace feeder and obtaining ofthe scaly particles of the melt flowing out of the spinneret, wherein,according to the invention, granite or rhyolite is used as a rock, priorto loading to the melting furnace the rock is heated up to temperaturebetween 750 and 950° C. and kept at this temperature during 20 to 30minutes until fracturing of conglomerates and removal of water vapors,then the rock is subjected to mechanical-catalytical activation untilobtaining particles of not more than 10 μm in size and is heated totemperature between 2110 and 2500° C. until obtaining the amorphousmelt, further homogenization and stabilization of the melt are performedin the melting furnace feeder at the temperature 1500 to 1750° C. untilobtaining the melt with viscosity being not less than 145 decipoise, andscaly particles are obtained by way of fracturing the melt streamflowing out of the spinneret.

The authors have experimentally determined the optimum operatingconditions for implementation of the methods of producing high-silicateinorganic continuous, staple fibers and fine scaly particles of rocks ofgranite or rhyolite type. In particular, in case of heating the rawmaterial up to temperature below 750° C. and keeping it for less than 20minutes, the quality of fibers and fine scaly particles so obtainedturns to be lower than required, because further obtained melt willcontain unmelted, fragile inclusions sparingly soluble in the melt,which significantly decrease the quality of the product obtained.Preliminary heating at the temperature over 950° C. during more than 30minutes is not justified economically. Obtaining the particles with thesize over 10 μm in the process of mechanical-catalytical treatment wouldcomplicate preparing of a homogenous melt and result in higher furthercosts for its heating in order to obtain the melt. Temperatures below2110° C. at the stage of obtaining the melt do not lead to removing mostof foreign solid inclusions, namely quartzites, from the melt andproducing the amorphous melt. Heating at the temperature over 2500° C.have practically no effect on quality of the product obtained and,therefore, is not justified economically. It is practically impossibleto produce homogenized and stable melt with optimum viscosity, i.e. notless than 145 decipoise, at the temperature below 1500° C., whileheating at the temperature over 1750° C. shortens the feeder andspinnerets service life because the melt contains substances whichobstruct the spinnerets.

The objective is also attained by the seventh variant of the proposedmethod, which, like the known method of producing high-silicateinorganic continuous fibers of rock, comprises operations of loadingfractured rocks to melting furnace, rocks melting, melt homogenization,further stabilization of melt in melting furnace feeder, fiber drawing,lubricating and winding onto a bobbin, wherein, according to theinvention, sand predominated rock with silicon oxide content equal orexceeding 73% is used as a rock, prior to loading to the melting furnacethe sand is heated up to temperature between 100 and 450° C. and kept atthis temperature during 30 to 60 minutes until removal of bound waterand gaseous inclusions, heated raw material is subjected tomechanical-catalytical activation until obtaining particles of not morethan 5 μm in size, then the raw material is heated up to temperaturebetween 2115 and 2550° C. and kept at this temperature until obtainingthe amorphous melt, homogenization and stabilization of the melt areperformed at the temperature 1440 to 1730° C. until obtaining the meltwith viscosity not less than 160 decipoise, and fibers are drawn fromthe melt zone located below the surface layer.

The objective is also attained by the eighth variant of the proposedmethod, which, like the known method of producing staple fibers of rock,comprises operations of loading fractured rocks to melting furnace,rocks melting, melt homogenization, further stabilization of melt inmelting furnace feeder, obtaining staple fiber from the melt flowing outof spinneret, wherein, according to the invention, sand predominatedrock with silicon oxide content equal or exceeding 73% is used as arock, prior to loading to the melting furnace the sand is heated up totemperature between 100 and 450° C. and kept at this temperature during30 to 60 minutes until removal of bound water and gaseous inclusions,heated raw material is subjected to mechanical-catalytical activationuntil obtaining particles of not more than 5 μm in size, then the rawmaterial is heated up to temperature between 2115 and 2550° C. and keptat this temperature until obtaining the amorphous melt, homogenizationand stabilization of the melt are performed in the melting furnacefeeder at the temperature 1440 to 1730° C. until obtaining the melt withviscosity not less than 160 decipoise, and staple fibers are obtained byway of inflating the melt flowing out of the spinneret.

The objective is also attained by the ninth variant of the proposedmethod, which, like the known method of producing high-silicateinorganic fine scaly particles of rock, comprises operations of loadingfractured rocks to melting furnace, rocks melting, melt homogenization,further stabilization of melt in melting furnace feeder and obtainingscaly particles from the melt flowing out of spinneret, wherein,according to the invention, sand predominated rock with silicon oxidecontent equal or exceeding 73% is used as a rock, prior to loading tothe melting furnace the sand is heated up to temperature between 100 and450° C. and kept at this temperature during 30 to 60 minutes untilremoval of bound water and gaseous inclusions, heated raw material issubjected to mechanical-catalytical activation until obtaining particlesnot more than 5 μm in size, then the raw material is heated up totemperature between 2115 and 2550° C. and kept at this temperature untilobtaining the amorphous melt, homogenization and stabilization of themelt are performed in the melting furnace feeder at the temperature 1440to 1730° C. until obtaining the melt with viscosity not less than 160decipoise, and scaly particles are obtained by way of fracturing themelt stream flowing out of the spinneret.

The authors have experimentally determined the optimum operatingconditions for implementation of the methods of producing high-silicateinorganic continuous, staple fibers and fine scaly particles of sandpredominated rock with silicon oxide content equal or exceeding 73%. Inparticular, in case of heating the raw material to temperature below100° C. and keeping it for less than 30 minutes, the quality of fibersand fine scaly particles so obtained turns to be lower than required,because further obtained melt will contain unmelted, fragile inclusionssparingly soluble in the melt, which significantly decrease the qualityof the product obtained. Preliminary heating at the temperature over450° C. during more than 60 minutes is not justified economically.Obtaining the particles with the size over 5 μm in the process ofmechanical-catalytical treatment would complicate preparing of ahomogenous melt, because large sand particles are tension concentratorsand result in higher further costs for heating in order to obtain themelt. Temperatures below 2115° C. at the stage of obtaining the melt donot lead to removing most of foreign solid inclusions from the melt andproducing the amorphous melt. Heating at the temperature over 2550° C.have practically no effect on quality of the product obtained and,therefore, is not justified economically. It is practically impossibleto produce homogenized and stable melt with optimum viscosity, i.e. notless than 160 decipoise, at the temperature below 1440° C., whileheating at the temperature over 1730° C. shortens the feeder andspinnerets service life because the melt contains active substancescausing destruction of feeder refractory materials into particles whichobstruct (block up) the spinnerets.

The objective is attained by the first variant of the proposedproduction line, which, like the known production line for implementingthe first, fourth and seventh variants of the method, comprises rockdosing unit, melting furnace, feeder equipped with the spinneret and thefeeder for outputting the fiber, mechanisms for applying a lubricant,winding the fiber onto bobbin, preservation and storing of the fibersobtained, and means for technological process monitoring and control,wherein, according to the invention, the production line furthercomprises the arrangement for mechanical-catalytical processing of theraw material, heat exchanger installed on the dosing unit for rockpreliminary heating, blending chamber, which comprises the case, bottom,adjustable valves on the input and output sides, intended for melthomogenization and stabilization, spinneret heater, while the input ofthe arrangement for mechanical-catalytical treatment of the raw materialis connected with the output of the rock dosing unit, and the output ofthe arrangement is connected with the melting furnace input, meltingfurnace output is connected with the blending chamber input, the outputof the blending chamber is connected with the feeder equipped withheated spinneret.

The objective is also attained by the second variant of the proposedproduction line, which, like the known production line for implementingthe second, fifth and eighth variants of the method, comprises rockdosing unit, melting furnace, spinneret for outputting the staple fiber,mechanisms for preservation and storing of the staple fibers obtained,and means for technological process monitoring and control, wherein,according to the invention, the production line further comprises thearrangement for mechanical-catalytical processing of the raw material,heat exchanger installed on the dosing unit for rock preliminaryheating, and means for inflating the melt stream flowing out of thespinneret, while the input of the arrangement for mechanical-catalyticaltreatment of the raw material is connected with the output of the rockdosing unit, and the output of the arrangement is connected with themelting furnace input, melting furnace output is connected with thespinneret.

The objective is also attained by the third variant of the proposedproduction line, which, like the known production line for implementingthe third, sixth and ninth variants of the method, comprises rock dosingunit, melting furnace, spinneret for outputting the high-silicateinorganic fine scaly particles, mechanisms for preservation and storingof the high-silicate inorganic fine scaly particles obtained, and meansfor technological process monitoring and control, wherein, according tothe invention, the production line further comprises the arrangement formechanical-catalytical processing of the raw material, heat exchangerinstalled on the dosing unit for rock preliminary heating, and means forfracturing the melt stream flowing out of the spinneret, while the inputof the arrangement for mechanical-catalytical treatment of the rawmaterial is connected with the output of the rock dosing unit, and theoutput of the arrangement is connected with the melting furnace input,melting furnace output is connected with the spinneret.

The objective is attained by the first variant of the proposedcontinuous fiber, which, like the known one, is produced of natural rockmaterials, and the fiber according to the invention is made of dacite orrhyodacite.

The objective is also attained by the second variant of the proposedcontinuous fiber, which, like the known one, is produced of natural rockmaterials, and the fiber according to the invention is made of graniteor rhyolite.

The objective is also attained by the third variant of the proposedcontinuous fiber, which, like the known one, is produced of natural rockmaterials, and the fiber according to the invention is made of sandpredominated rock with silicon oxide content equal or exceeding 73%.

The objective is attained by the first variant of the proposed staplefiber, which, like the known one, is produced of natural rock materials,and the fiber according to the invention is made of dacite orrhyodacite.

The objective is also attained by the second variant of the proposedstaple fiber, which, like the known one, is produced of natural rockmaterials, and the fiber according to the invention is made of graniteor rhyolite.

The objective is also attained by the third variant of the proposedstaple fiber, which, like the known one, is produced of natural rockmaterials, and the fiber according to the invention is made of sandpredominated rock with silicon oxide content equal or exceeding 73%.

The objective is attained by the first variant of the proposedhigh-silicate inorganic fine scaly particles, which, like the knownones, are produced of natural rock materials, and the particlesaccording to the invention are made of dacite or rhyodacite.

The objective is also attained by the second variant of the proposedhigh-silicate inorganic fine scaly particles, which, like the knownones, are produced of natural rock materials, and the particlesaccording to the invention are made of granite or rhyolite.

The objective is also attained by the third variant of the proposedhigh-silicate inorganic fine scaly particles, which, like the knownones, are produced of natural rock materials, and the particlesaccording to the invention are made of sand predominated rock withsilicon oxide content equal or exceeding 73%.

The proposed method may be implemented in case of use of acidic rock asraw material, such acidic rock being dacite or rhyodacite, granite orrhyolite, and also sand predominated rock with silicon oxide contentequal or exceeding 73%, while said rock proportion in the volume of rawmaterials input to the production line exceeds 70%.

The raw material used, i.e. fractured rock, has various inclusions, alsothe inclusions with melting point over 1400° C. The influence of theseinclusions on the obtained product may be observed, in most of cases,only after producing the fibers. Therefore, it is very important toremove these inclusions prior to production of continuous, staple fibersand fine scaly particles. Sometimes said inclusions are present in theraw material in a bound form, therefore, exposing it tomechanical-catalytical treatment enables breaking of the bounds betweenthe substances in the parent material containing foreign inclusions andprepares the raw material to their removal. In case of heating at thetemperature approximately 1200 to 1400° C., such inclusions may remainin the melt. But the experiments have proved that most of saidinclusions decompose when the melt temperature is increased to2100-2550° and the melt is kept at this temperature during 10 to 60minutes. The idea of the proposed solution is to create conditions forweakening of the crystal lattice of the fractured rock i.e. rawmaterial, by way of its mechanical-catalytical treatment and furtherquick heating up to the temperatures exceeding 2100° C.

Among the natural acidic rock materials the proposed materials have thefollowing chemical composition (see Table 1).

High content of silicon oxide, high melting and boiling temperatures ofthe mentioned materials enable their use for producing very strong,temperature and corrosion resistant fibers, because upon attainingmelting temperatures of these materials it becomes possible to removeunwanted impurities, which have lower melting points, block up thespinnerets used in forming continuous, staple fibers and fine scalyparticles.

In order to ensure better mixing of the melt and removing gaseousinclusions, the blending chamber is positioned 1.2 to 2.5 m lower thanthe furnace bottom, from where the melt falls down vertically tohorizontal plate of the blending chamber. As a result, the melt is mixedmore intensively and gaseous inclusions are released more actively. Thelevel of the melt in blending chamber is maintained 2.0-2.5 higher thanin the furnace. This condition ensures constant hydrostatic pressure atthe spinnerets and preserves heat, thus, bringing the process ofproducing the fibers closer to adiabatic conditions.

The proposed variants of production line are characterized in that thefeeder is equipped with fittings for discharging the melt from thefeeder. With a view to the fact that this technology comprises the useof high temperatures, the refractory materials of furnace, feederblending chamber may be destroyed into particles, which are dischargedoutside through drain fittings located at the feeder edges in order toprevent their ingress to spinnerets.

Ball mill (BM), disintegrator (DI), and velocity layer apparatus (VLA)were used as the arrangement for mechanical-catalytical treatment of rawmaterials in the proposed variants of the production line.

BRIEF DESCRIPTION OF THE DRAWINGS

The essence of the invention is further explained by the drawings,where:

FIG. 1 schematically illustrates the proposed production line forproducing high-silicate continuous, staple fibers and fine scalyparticles of acidic rock minerals.

FIG. 2 schematically illustrates the production line for producingcontinuous fibers.

FIG. 3 schematically illustrates the production line for producingstaple fibers.

FIG. 4 schematically illustrates the production line for producingcoarse fibers.

FIG. 5 schematically illustrates the production line for producing finescaly particles.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Each variant of the proposed production lines comprises tanks 1 forstoring acidic rocks, dolomite, limestone and other components, heatexchanger 2, dosing unit 3, mechanical-catalytical activator 4, mineralsloader 5, melting furnace 6, draining unit 7, draining fitting 8,adjustable valve 9, horizontal blending chamber 10, which includesinclined platform 11, accumulating pool 12 with barbotage nozzles 13built in, burners 14, antifoam baffle 15, melt stabilization pool 16,feeder 17, working units 18, spinnerets with (plates) feeders 19,through which the continuous fibers (ContF), staple fibers (SF), andcoarse fibers (CoarF) are drawn. Working units, feeder, blending chamberare further equipped with the heating systems 20. Heat exchanger 2 isconnected with the furnace melting space 6 and horizontal blendingchamber 10.

In order to stabilize the process of fibers drawing the production lineincludes the arrangement for their treatment immediately upon exitingfrom the spinnerets by air-water helium sprays (not shown). For thepurpose of ContF manufacturing the production line comprises themechanism for applying the lubricant 21 onto the fibers and bobbin 22for winding the fibers. For the purpose of SF production the spinneretplate 23 made of heat resistant alloy or ceramics is installed in theworking unit. The melt level is maintained at the defined level over it,and primary fibers are drawn using the mechanism 24, then they areinflated by the hot gases stream (HG) to obtain SF. Also the staplefibers were obtained immediately upon preparing the melt in the furnace6, which was fed to inflation head 25 and turned into SF.

In order to obtain coarse fibers, heat resistant feeder 26 was alsoused. It was heated by electric current. Formed streams of melt aredrawn into fibers by compressed air flow using a blower. Fiber-formingunit 27 has the shape of truncated pyramid. Coarse fibers are depositedin fiber deposition chamber 28 at the netting of the conveyor withbreaking unit 29 located at its end. The unit 29 divides the CoarF intosegments of the defined length, which are then packed in the packaging30.

For the purpose of obtaining the CoarF of the specific diameter andlength, which are used, for example, in concrete dispersedreinforcement, the working unit comprise adjustable valve that may beinstalled to corresponding melt level using electric drive.

In order to create a protective film on the CoarF surface, the fiberswere chemically treated in the chamber 31.

Inorganic fine scaly particles (hereinafter referred to as “the scales”)are produced using one of the fittings 32 for discharging the melt fromthe feeder with telescopic pipe 33 rigidly connected to such fitting,the second tube 34 is installed movable on the first pipe 33, the upperend of the second tube 34 is intended for intaking the melt from thefeeder 17, and the first pipe 33 lower end is used for outputting themelt onto the working surface 35 of rotating fine forming element 36.Fine forming element 34 is made as a cone with the vertex orientedtowards discharging orifice (fitting) 32.

The melt stream flows through the orifice 32 to working surface 35 ofthe rotating element 36, where, being influenced by centrifugal force,turns into a thin film. At the moment of melt moving in the form of thinfilm, said melt film hardens at the surface edge being influenced by gasflow from output 38 of ring blow head 37. Along with that(simultaneously) the gas stream, coming out of output 39, disperses thehardened film into many scaly particles. The particles thickness isregulated by means of a drive kinematically linked with the tube 34.

Ball mill ShM 900×1800 filled with quartz balls was used as thearrangement for mechanical-catalytical activation. In the process ofdrum rotation the balls rubs against its walls and rise to a certainheight, then they fall freely crushing the raw material by kicks andattrition. The raw material may be fractured using wet or dry method. Inthe first case the suspension is freely poured though a hollow journal,and in the second case the crushed material, being influenced by the ownweight, is unloaded though the journal to minerals loader 5. BM is usedfor the raw material modification by dolomite, limestone and theirmixture as swell as other modificators, for example Cr₂O₃, which resultsin higher strength of high-silicate fibers obtained. This phenomenon maybe explained by formation of modificator absorption layer on theminerals surface. Such layer facilitates formation of absorption andchemical bound between modificator and minerals particles.

Rocks are comprised of crystals having different granularity, i.e.druses. BM are usually utilized to destroy them. In a BM druses arekicked and rolled by balls and, thus, crushed.

Disintegrator was also used as the arrangement formechanical-catalytical treatment of raw materials, where the rawmaterial is crushed due to quick rotation of fingers. UDA typedisintegrator enables creation of defects in the structure of mineralgrains under high rotor RPMs, and such defects result in higher furnacecharge reactivity and shorter melting time. During raw materialscrushing in disintegrator mechanical-chemical processes occur not onlyon freshly formed surfaces but also in the volume of crystals crushed.These processes primarily cause formation of a big number of vacanciesthat lead to altering of a number of physical (mechanical) and chemicalproperties of crushed crystals. For instance, the melting point andsolubility of acidic rock crystals decrease. Mechanical-catalyticaltreatment results in formation of not merely a crushed substance withthe same characteristics as original one, but rather a new substancehaving different physical and physicochemical properties.

Mechanical-catalytical treatment of raw materials was also performed invelocity layer apparatus (VLA), where crushing and activation areattained by using metal solids rotating in a magnetic field. Big SiO₂particles would become crystallization centers in the melt and tensionconcentrators in the future product. Therefore, SiO₂ crushing in VLAresults in activation not only due to increasing of specific surfacearea but also due to more lattice imperfection. In fact, the activitygrows not only at the surface but in the particles volume, too, which isattributable to formation of so called “active lattice” as a result ofbreaking Si—O bound. Ultimately, this shortens the melting time andimproves the fibers strength and homogeneity. It was found thatmechanical activation results in decreasing of solid phase reactionstemperature and performing reactions, which were not observed withoutactivation. Mechanical-catalytical treatment of acidic rocks decreasesthe melting temperature, accelerates the process of producing glass melthomogenous in terms of contents and temperature, and, thus, enablespreparing of the melt for obtaining high-silicate inorganic fibershaving excellent properties.

EXAMPLE 1

Continuous fiber production. Dacite (D) was used as a rock. Prior to Dloading to the melting furnace 6 (see FIG. 2) it was heated up to thetemperature 810° C. on the average and kept at this temperature during10 minutes on the average until removal of chemically bound water andburning up organic components. Then the raw material was loaded todisintegrator 4, fractured to 15 μm size and gradually fed to thefurnace 6 through loader 5. In the furnace the material was heated up tothe temperature 2150° C. in order to obtain anorphous (96%) melt. Notmelted particles (mostly, quartzites) were discharged though fitting 8.Further homogenization and stabilization of the melt were performed inthe blending chamber 10 and feeder 17 at the temperature 1420 to 1710°C. After that the melt was fed to working unit 18 located overspinnerets 19, through which the continuous fibers were drawn. Thefibers obtained were lubricated using roll arrangement 21. Then thefibers were wound onto bobbins 22. The samples of fibers were taken andtested to determine their strength, heat resistance. The fibers diameterwas measured according to GOST [State Standard] 6943.2-79, tensile testswere performed subject to GOST 6943.5-79. The fibers chemical resistanceto HCl 2 N solution was determined by measuring the mass lost from the 5000 sq.cm surface after 3 hours of boiling. The test results aresummarized in Table 2. The test results have shown that the continuousfibers produced according to the proposed method on the proposedproduction line have higher tensile strength, heat and chemicalresistance compared to fibers obtained using the prior art method.

EXAMPLE 2

Continuous fiber production. The operations described in the Example 1were performed except that rhyodacite was used as raw material. Theproperties of produced continuous fibers are presented in Table 2. Thedata clearly indicate that the fibers obtained excels the prior artfibers in a number of characteristics.

EXAMPLE 3

Continuous fiber production. Granite was used as a raw material. Priorto granite loading to the melting furnace 6 it was heated up to thetemperature 950° C. and kept at this temperature during 25 minutes untilfracturing of conglomerates and removal of water vapors and carbonoxide. Then the raw material was subjected to mechanical-catalyticalactivation in disintegrator 4 until the particles of not more that 10 μmin size were obtained. Obtained material was heated in the furnace 6 upto the temperature 2450° C. to yield amorphous melt containing noparticles of unmelted mineral phases. Homogenization and stabilizationwere performed in the horizontal blending chamber and feeder at thetemperature 1500 to 1750° C. After that the melt was fed to working unit18, where feeders with spinnerets 19 were installed. Continuous fiberswere drawn through the spinnerets.

The continuous fiber so obtained was tested to determine its strength,chemical and thermal resistance. The test results are given in Table 2.The data contained in Table 2 indicate that fibers obtained of granitehave characteristics not worse than those of fibers according to thestate of the art.

EXAMPLE 4

Continuous fiber production. The operations described in the Example 3were performed except that rhyolite was used as raw material.Specifications of continuous fibers produced are presented in Table 2.

EXAMPLE 5

Continuous fiber production. The raw material used was a rock comprisingmostly sand with silicon oxide content equal or exceeding 73%. Sandratio in the rock was 60 to 95% w/w, rest of material was a mixture oflimestone and dolomite. The optimum mixture was one containing 70 to 90%w/w of sand, and the most preferred mixture had sand content 75 to 85%w/w. Amount of limestone and dolomite mixture is 5 to 40% w/w. Desirableproportion of limestone and dolomite mixture is 10 to 30% w/w, while themost preferred range is 15 to 25% w/w. Usually the mixture contains 12to 40% w/w of limestone and 2 to 15% w/w of dolomite. It is desirablefor these mixtures to contain 14 to 30% w/w of limestone and 3 to 12%w/w of dolomite. The most preferred ranges are 15 to 25% w/w and 4 to11% w/w, correspondingly. Prepared furnace charge was heated up to thetemperature 350° C. and dried during 40 minutes in order to removehydrotechnical water and gaseous inclusions. Than the raw material wassubjected to mechanical-catalytical activation in velocity layerapparatus 4 until the particles of not more than 5 μm in size wereobtained. After that the raw material was heated in furnace 6 up to thetemperature 2380° C. and kept at this temperature until rock grains,crystals were destroyed and amorphous melt was obtained. Melthomogenization and stabilization were performed in horizontal blendingchamber and feeder at the temperature 1440 to 1730° C. until the melt,having viscosity 160 decipoise, was produced. Then the melt flowed tothe working unit installed over spinnerets, from which the continuoushigh-silicate fiber was drawn.

Physicochemical properties of inorganic fibers produced of modifiedsands are presented in Table 2. The data indicate that the fibersobtained are not yielding to fibers obtained according to the state ofthe art method.

EXAMPLE 6

Staple fibers production. The operations described in the Example 1 wereperformed except that, starting from the stage of fibers drawing fromspinneret plate 23 using special mechanism 24, the fibers were inflatedby hot gases stream to become staple fibers (see FIG. 3). Specificationsof high-silicate staple fibers produced are presented in Table 3.

EXAMPLE 7

Staple fibers production. The operations described in the Example 6 wereperformed except that rhyodacite was used as raw material.Specifications of staple fibers obtained are presented in Table 3.

EXAMPLE 8

Staple fibers production. The operations described in the Example 6 wereperformed except that granite was used as raw material. Properties ofhigh-silicate staple fibers produced are presented in Table 3.

EXAMPLE 9

Staple fibers production. The operations described in the Example 6 wereperformed except that rhyolite was used as raw material. Results aregiven in Table 3.

EXAMPLE 10

Staple fibers production. The operations described in the Example 6 wereperformed except that raw material used was a furnace charge containing75 to 85% w/w of sand with SiO₂ content equal or exceeding 73%, 15 to25% w/w of limestone and 4 to 11% w/w of dolomite. Results are given inTable 3.

EXAMPLE 11

Coarse fibers production. The operations described in the Example 1 wereperformed except that, starting from the fiber drawing stage, the formedstreams of melt are drawn into fibers by compressed air flow using ablower 27 (see FIG. 4). Coarse fibers were deposited in fiber depositionchamber 28 and broken into segments of specific length in the unit 29.Technical data for high-silicate coarse fibers produced are presented inTable 4. The data contained in Table 4 indicate that coarse fibersobtained have characteristics not worse than those of fibers producedusing the state of the art method.

EXAMPLE 12

Coarse fibers production. The operations described in the Example 11were performed except that rhyodacite was used as raw material.Specifications of coarse fibers obtained are presented in Table 4.

EXAMPLE 13

Coarse fibers production. The operations described in the Example 11were performed except that granite was used as raw material. Technicaldata for coarse fibers produced are presented in Table 4.

EXAMPLE 14

Coarse fibers production. The operations described in the Example 11were performed except that rhyolite was used as raw material. Resultsare given in Table 4.

EXAMPLE 15

Coarse fibers production. The operations described in the Example 11were performed except that furnace charge consisting of sand and mixtureof limestone and dolomite was used as raw material. Specifications ofcoarse fibers produced are presented in Table 4.

EXAMPLE 16

Fine scaly particles production. To produce fine scaly particles, theoperations described in Example 1 were performed except that the meltstream through the orifice 32 was fed to the working surface 35 of therotating element 36, where, being influenced by centrifugal force, thestream turned into a thin film. At the moment of melt moving from therotating element, the melt in the form of thin film was dispersed intomany scaly particles using the ring blow head. Technical data forhigh-silicate scaly particles produced of dacite are presented in Table5. The data contained in Table 5 indicate that scaly particles obtainedhave characteristics not worse than those of scaly particles producedusing the state of the art method.

EXAMPLE 17

Fine scaly particles production. The operations described in the Example16 were performed except that rhyodacite was used as raw material.Specifications of scaly particles produced are presented in Table 5.

EXAMPLE 18

Fine scaly particles production. The operations described in the Example16 were performed except that granite was used as raw material.Technical data of scaly particles produced of granite are presented inTable 5.

EXAMPLE 19

Fine scaly particles production. The operations described in the Example16 were performed except that rhyolite was used as raw material. Thetest results are given in Table 5.

EXAMPLE 20

Fine scaly particles production. The operations described in the Example12 were performed except that furnace charge consisting of sand andmixture of limestone and dolomite was used as raw material. Theexperiments carried out enabled to attain increase in output of fineparticles of the given fraction. The particles thickness was regulatedby way of changing the melt level fed to the working surface 35 of therotating element 36 with the use of electric drive kinematically linkedto the tube 34 intended for intaking the melt from the feeder 17.Deviation K of particles diameter is determined as a ratio of particleellipse minor axis to its major axis. Specifications of scaly particlesproduced are presented in Table 5.

The continuous, staple, coarse fibers and scaly particles so obtainedwere tested to determine their acid and thermal resistance and tensilestrength. The test results are given in Tables 2, 3, 4 and 5.

The test results have shown that the products obtained according to theproposed methods on the proposed production lines have approximately15-32% higher acid resistance and tensile strength compared to productsobtained using the prior art methods. These characteristics wereattained due to creation of conditions for removal of high meltingtemperature inclusions from the melts.

The proposed inventions may be used in operations with other minerals(ultrabasic, basic, medium and sand varieties) with temperatures ofmaterial subjected to drawing not exceeding the temperatures indicatedin the present invention.

TABLE 1 Limit chemical component contents in the rock, in % w/w SamplesAverage chemical component contents, in % w/w No. Rock descriptionquantity SiO₂ Al₂O₃ Fe₂O₃ FeO TiO₂ MnO 1 Dacite 6 67.80-68.9515.36-15.48 1.97-2.16 2.07-2.97 0.41-0.43 0.07-0.11 67.9  15.4  2.082.37 0.42 0.09 2 Rhyodacite 5 68.52-71.9  14.6-15.1 0.91-1.85 1.24-1.920.25-0.52 0.12-0.18 71.2  14.9  1.79 1.69 0.37 0.17 3 Granite 670.18-72.83 14.1-15.2 0.18-2.52 0.62-2.12 0.19-0.49 0.08-0.1  72.1214.75 1.32 1.52 0.31  0.095 4 Rhyolite 5 73.01-77.42 12.92-14.911.05-1.35 0.52-1.95 0.08-0.29 0.03-0.08 74.34 13.98 1.04 0.68 0.19 0.045 Sand from 12 88.3-96.8 — — — — — Didivskyi deposit 95.8  Limitchemical component contents in the rock, in % w/w Average chemicalcomponent contents, in % w/w No. CaO MgO K₂O Na₂O SO₃ P₂O₅ other Total 1 3.6-3.63 0.93-1.24 2.83-2.96 2.94-3.08 0.1-0.2 0.1 0.49-0.69 3.61 1.042.88 2.99 0.13 0.1 0.58 99.6 2 0.49-3.09 0.59-1.81 2.81-5.89 1.79-4.810.019 0.021 0.16-0.51 1.92 1.19 3.59 3.05 0.019 0.021 0.29 100.2 30.51-2.99 0.47-1.21 2.88-6.01  1.7-4.55 0.01 traces 0.39-0.74 1.79 0.984.05 2.98 0.01 0.5  100.4 4 0.41-1.84 0.61-0.98 3.31-3.91 2.14-4.14traces 0.01 0.65-1.0  1.41 0.41 3.11 3.97 0.01 0.83 100 5 — —  0.1-0.980.09-0.81 0.04-0.6  — 1.44-1.59 0.89 0.75 0.58 1.51 99.64

TABLE 2 Fiber Chemical resistance Utilization diameter, in Tensilestrength, in 2N HCl (98° C., 3 temperature, in No. Rock description μmin MPa hours), in % ° C. 1 Dacite [1] 5.6-12.4 2490 92 700-865 2Rhyodacite [2] 5.3-12.7 2550 92.8 720-880 3 Granite [3] 5.5-11.8 261093.7 750-920 4 Rhyolite [4] 4.7-12.5 3115 95.2  880-1050 5 Sands withSiO₂ 3.8-13.8 2350 91.1 600-720 content ≧ 73%, [5] 6 State of the art5.8 2300 90.8 600-710

TABLE 3 Rock description (number) State of the No. Staple fiberproperties 1 2 3 4 5 art 1 Fiber length, in mm 10-45 12-40 15-42 12-4410-40 10-40 2 Non-fibrous inclusions quantity, 1.9-4.8 2.0-4.9 1.9-4.81.8-5.0 2.0-4.9 2-5 in % 3 Utilization temperature, in ° C. 865 880 9201050 855* 700 4 Hygroscopicity, in % 0.45 0.41 0.35 0.2 0.88 1*Short-term

TABLE 4 Rock description (number) Known TU [Technical No. Coarse fiberproperties 1 2 3 4 5 specifications] 023.005-89 1 Fiber diameter, in μm130 135 125 120 110 115 + 35  2 Length, in mm 70 75 70 75 70 75 + 25 3Tensile strength, in MPa 285 287 295 305 210 200 4 Alkali resistance, in%, 93.1 92.5 92.1 91.7 90.5  90 not less than

TABLE 5 Rock description (number) State of No. Scaly particlesproperties 1 2 3 4 5 the art 1 Thickness scattering for 100 2.8 2.9 2.92.8 3 3 particles, in μm, up to 2 Deviation, K 0.85-0.96 0.81-0.960.83-0.95 0.84-0.95 0.81-0.95 0.8-0.95 3 Resistance in 2N HCl (98° C., 391.8 92.1 93.1 95.3 90.9 77.6** hours), in % **Berestovetsk basaldeposit

1. The method of producing continuous inorganic fibers of rock,comprising operations of: loading fractured rocks to a melting furnace,melting the rocks to produce a melt, homogenizing the melt, furtherstabilizing the melt in a melting furnace feeder, drawing a fiber, andlubricating and winding the fiber onto a bobbin, wherein dacite orrhyodacite is used as a rock, prior to loading to the melting furnacethe rock is heated up to temperature between 700 and 910 ° C., kept atthis temperature during 5 to 15 minutes until removal of chemicallybound water and burning up organic components, then the rock issubjected to mechanical-catalytical activation until obtaining particlesof not more than 15 μm in size and is heated to temperature between 2105and 2200 ° C. until obtaining the melt with amorphism degree of not lessthan 96% and isolation of not melted quartzites from the melt, furtherhomogenization and stabilization of the melt are performed at thetemperature 1420 to 1710 ° C. until obtaining the melt with viscositybeing not less than 130 decipoise, and fibers are drawn from the meltbelow a surface thereof.